We can communicate on this board until they kick us out - or else change to E-mail.
Self-publishing i s interesting and has become affordable in Germany as well. My father-in-law just published his memoires in paperback (15 x 21 cm, 230 pages b/w, coloured cover), and it cost him like 7 Euros per copy. But of course he doesn't want to really sell it, he gives the copies away to his children and grandchildren etc.
A friend and I published a songbook with Hebrew songs 15 years ago this same way (there was no digital print then though) and we have been selling it basicly by mail (and a few bookstores in Germany). We've been on the net for a year now (www.aschira.de) and we are doing fine: We have sold almost 10.000 copies altogether plus cassette tapes and CDs. So if your product is good it will sell.
So what will make your book a good book? Do you know many American name books? Any good ones? All I have is Kolatch's Dictionary of First Names (with a big baby on the cover) and most of it is crap. But I'm sure it sells. So your book can only be better (and hopefully do even better). What languages do you know? You must be into languages somehow, even though you're "mathematical" - or else you wouldn't want to write this book.
I'm afraid in Germany there are quite a number of good name books and if I should recommend one (besides my own, ha ha!), I would say: "Das große Vornamenlexikon" Duden Verlag, ISBN 3-411-06082-4. Of course it is in German, but with a little help from your husband ...
Actually my family and I live a four hours' drive from Munich, going west. Maybe you can find the city of Kaiserslautern on a map, it's not far from the French border. Now we live 30 km south of it, and if you happen to come to Germany, do drop in!